Acetylene transport system



oct- 29, 1963 H. J. PoRTzL-:R ETAL 3,108,445

ACETYLENE TRANSPORT SYSTEM Filed July 14, 1958 COOLING 7' HEATING MEDIUMINVENTORS HARRY J. PORTZER HERBERT B. SARGENT MARTIN L. KASBOHM EARL A.BOHNER,JR.

ATTORNEY United States Patent O 3,103,445 AQETYLENE TRANSPORT SYSTEMHarry J. Portzer, Herbert B. Sargent, Martin L Kashohm,

and Earl A. Bohnen', Jr., all of indianapolis, Ind., assignors to UnionCarbide Corporation, a corporation oli New York Filled .inly 14, i953,Ser. No. '743,326

7 Claims. (Cl. S2-48) This invention relates to a method of storing andtransporting acetylene. More particularly this invention relates to asystem for the safe and economical storage and transport of acetylene inliquid or solid form.

The commercial process currently in use for storing and shippingacetylene is one in which the acetylene is stabilized by dissolving itin a solvent such as acetone. The dissolved acetylene containercomprises a metal vessel (cylinder) illed with a porous solid material,usually called a iiller, and a quantity of acetone. Acetylene gas isthen dissolved in the acetone under pressure. The solvent and filler arerequired to stabilize the acetylene since acetylene gas under pressureis subject to the initiation of exothermic decomposition. This transportsystem has the disadvantage of discharging acetylene contaminated withminor amounts of acetone.

The dissolved acetylene cylinder is a costly way of storing and shippingthis gas because the acetylene itself makes up only a small fraction ofthe total weight of the package. For the dissolved acetylene cylindersin current commercial use the acetylene represents only about 10 percentof the total weight.

lt is the main object of this invention to provide a safe and efficientmethod for the storage and transport of acetylene which is not subjectto the disadvantages of` the present commercial process as pointed outabove.

It is a further object of this invention to provide a package for thesafe storage of acetylene which does not require the use of a solvent.

It is a still further object of this invention to provide a means forthe safe storage and transport of liquid and solid acetylene.

In the drawing, FlGS. 1-4 are horizontal sectional views of fourembodiments of the present invention suitable for the storage andtransport of relatively small amounts of acetylene, and

FIG. 5 is a longitudinal sectional view of an embodiment of thisinvention suitable for the storage and transport of acetylene on acommercial scale.

According to the present invention, liquid or solid acetylene isrendered inert and safe for storage or transport by introducing theacetylene into the pores of a solid stabilizing medium. The presentinvention also provides etiicient and safe methods for introducing theacetylene into the porous stabilizing medium and withdrawing theacetylene from the stabilizing medium. The porous medium stabilizes theacetylene by preventing a potential progressive decomposition induced byinitial decomposition of small amounts of acetylene resulting from heator external shock.

The apparatus of this invention includes a closable vessel containing aporous stabilizer in whose pores liquid or solid acetylene can be storedand which also contains a space or highly permeable medium between theporous stabilizer and the vessel walls. This latter feature provides apath for acetylene during charging and discharging of the vessel. Exceptpossibly during charging, the vessel wall is kept warmer than theinterior so that no condensed acetylene remains in the space or highlypermeable medium next to the wall. Tests show that a porous stabilizer,such as monolithic calcium silicate filler, when used in this way, givesan exceptional degree of stability to condensed acetylene.

If the stabilizing effect of the porous stabilizer is made so great thata progressive decomposition cannot be propagated through the containedliquid acetylene, all of the porous stabilizer can safely be saturatedwith liquid or solid acetylene. If the stabilizing effect is less thanthis, the condensed acetylene in the central part of the container isprotected against decomposition initiating influences from the outsideby a barrier layer. This barrier layer may be the outer part of theporous stabilizer which is not iilled with condensed acetylene, or itmay be a separate layer of more permeable material, such as foamplastic. In either case the pores of this barrier layer are filled withgaseous acetylene.

The handling process of this invention comprises introducing gaseousacetylene into a porous stabilizing medium while the medium ispreferably cooled by means of imbedded cooling means such as coils 0rplates. Gaseous acetylene may then be vaporized and discharged bypassing warm fluid through the same imbedded coils or plates. In thisfashion gaseous acetylene is both introduced and withdrawn from thecontainer eliminating the necessity for handling liquid or solidacetylene in an unstaoilized form.

The porous, solid stabilizers of this invention prevent the explosivedecomposition of solid or liquid acetylene by providing heat-absorbingmaterial close to each part of the acetylene lying within the pores ofthe stabilizer. Heat liberated by the decomposition of any part of theacetylene is quickly absorbed by the stabilizing medium and no generaldecomposition or explosion of the acetylene can take place.

To be useful asa stabilizer against the progressive decomposition ofsolid or liquid acetylene the porous, solid material should have amajority but not necessarily all of the following characteristics.

(a) It should be chemically inert toward acetylene and the materials ofthe container and the heat-transfer coils or plates at the conditions ofservice the function of heattransfer coils or plates is discussedhereinbelow);

(b) lt should not promote the polymerization of acetylene;

(c) It should not be soluble in liquid acetylene, nor lose its desiredphysical structure in contact with acetyene;

(d) It or its decomposition products should have a high capacity forabsorbing heat in the temperature range from about -82 C. (melting pointof acetylene) to about G C. (critical temperature for propagation ofacetylene decomposition tiame);

(e) if it decomposes or reacts with other components at temperatures upto the critical temperature for propagation of acetylene decompositionflame, the decomposition or reaction should be as stronglyheat-absorbing as possible.

(f) If it changes state in heating up to the critical temperature ofacetylene decomposition ame, the heats of transition should be large.

Not only should the composition of the porous stabilizer be such thatits potential stabilizing effect is great, but also its physical formshould be such that its potential stabilizing effect is largelyrealized. The pore size is important for two reasons. First, the poresmust be small enough so that the liquid acetylene will not drain fromthe porous stabilizer by gravity, but rather will be held within thecentral region of the package by capillary action. Second, the poresmust be small enough so that the acetylene within them is effectivelystabilized against decomposition. The mechanism by which liquidacetylene is stabilized by a solid material depends, in part at least,on the transfer of heat from hot acetylene and/ or its products ofdecomposition to the solid material. If

some of the acetylene is heated by any means to a high temperature, heatcan be absorbed by the stabilizing material quickly enough so that anyincipient decomposition wave is destroyed, and no wide-spreaddecomposition of the acetylene can occur. It has been found that forsatisfactory stability in the subject system the pores should have amaximum cross-sectional dimension between about 0.005 and 50 microns.The pores should be inter-com nected and at least some of them shouldhave a diameter approaching the large end of this range in order thatcharging and discharging will not be ditiicult. The particles thatcomprise the porous stabilizer must be of such shape and size as toprovide enough pores of the desired size to accommodate the liquidacetylene.

Examples of materials which, when in the proper state of subdivision toprovide pores having a maximum crosssectional dimension of about 0.005to 50 microns, are useful as stabilizing media for solid or liquidacetylene are alumina trihydrate, calcium carbonate, silica, carbon andmonolithic calcium silicate filler of the types described in U.S.2,422,251 issued lune 17, 1947 and copending application Serial No.351,478 tiled April 27, 1953, now Patent No. 2,883,040, by A. S. Paterand J. W. Houser. This calcium silicate filler contains inert mineralliber such as asbestos in order to form a strong, crackfree monolithicmass. Solid carbon dioxide and finely divided solid water would also beoperable, but the use of these materials would require extra care inmaintaining the acetylene package at low temperatures at all times, evenwhen not containing acetylene.

A solid stabilizer which can be prepared in the form of a monolithicmass such as the calcium silicate filler referred to hereinabove, ispreferable because such a stabilizer retains its shape and may be easilypositioned within the closable shell of the vessel. We have found thatsuch calcium silicate filler contains pores and internal cracks havingdiameters in the range of about 0.01 to 1.0 micron and providesexcellent stabilization for acetylene condensed therein. A powderedstabilizer, such as finely divided carbon, would require more elaborateconstruction details in the gas package; for example, the powderedmaterial may be held in place by a layer of foam plastic which alsoserves as the highly permeable barrier.

Also, for economic reasons the stabilizer should be chosen so that theratio of the weight of the stabilizer to the weight of condensedacetylene within the stabilizer is as small as possible, whilemaintaining stability against progressive decomposition. For example,when monolithic calcium silicate is used as the stabilizer, theacetylene is stable to the externally applied shock of explodingdynamite when the stabilizer/ acetylene weight ratio is about one orgreater.

The present invention in its simplest form comprises a vessel filled,except for a space 11 next to the wall, with a homogeneous, porousstabilizer l2 and a valve 13 through which acetylene can be put in ortaken out (FG. 1). If the stabilizing effect of the porous stabilizer isso great that the liquid or solid acetylene in the pores of the porousstabilizer is not subject to progressive decomposition, all of the poresin the porous stabilizer can safely be filled With liquid acetylene forstorage or transport. If the stabilizing effect is less than this, anouter layer 14 of porous stabilizer 12 can be freed of part or all ofits liquid acetylene (FIG. 2). In either case the space l1 next to theWall is free of liquid or solid acetylene during storage and transportby virtue of heat that enters through the wall.

This vessel can be charged with acetylene generally in two differentways. First, liquid acetylene can be introduced directly to thecontainer. This involves the hazard of handling liquid acetylene in arelatively unstable form. Second, gaseous acetylene can be introducedand condensed in situ; this is the preferred charging method. Thislatter method involves cooling the container below 4 the condensationtemperature of acetylene, the particular condensation temperature beingdependent on the pressure at which the gaseous acetylene is supplied tothe container. Cooling can be obtained by either external or internalmeans, with internal cooling coils or plates being preferred.

The forms illustrated in FIGS. 1 and 2 have the disadvantage whenprecooled below acetylene condensation temperature that during chargingthe space 1l next to the 'all contains liquid acetylene that is notstabilized; this introduces an element of hazard into the chargingoperation and also interferes with free flow of gaseous acetylene to thewhole surface of the body of porous stabilizer. In a preferred form ofthe invention heat is removed from the container during charging bypassing cooling iluid through a heat conducting means 15 imbedded in theporous stabilizer (see FIG. 3). A helical coil is shown for purposes ofillustration, but a plate containing internal passages is equallysatisfactory. During discharging, heat is added by passing warming fluidthrough the same passages. Charging and discharging are facilitated byhaving each passage in the form of a fiat spiral disposed so that theturns are roughly concentric with the vessel wall. In one embodiment ofthe invention the inner end of the spiral tube is brought out along aradius to the outside as shown in the figure. In another ernbodiment ofthe invention, several liat spirals disposed generally parallel to oneanother may be manifolded to inlet and outlet tubes, such tubes beingdisposed essentially perpendicular to the planes of the ilat spirals.One tube, near the outer surface of the porous stabilizer mass connectswith the outer (large radius) end of the spiral passages and anothertube, near the center of the porous solubilizer mass, connects with theinner (small radius) end of the spiral passages. This latter embodimentis advantageous in packages of industrial size where several heattransfer tubes or plates may need to be imbedded in the porousstabilizer in order that the rates of charging and discharging will beadequate. During charging, cooling fluid can be brought to the center ofthe container through the radial end of the tube or central manifold andled to the outside through the spiral end, thus producing a temperaturegardient from the cooler center to the warmer surface of thedecomposition-inhibiting solid. ln this way the zone containing liquidacetylene increases from the center outward as filling proceeds. Thisleads to an orderly complete filling. When the central part of hecontainer is full of liquid, a layer of gas-filled porous stabilizersurrounds the liquid-filled porous stabilizer, a condition that may bedesired for safety.

When the acetylene is to be discharged, warming fluid can be introducedthrough the outer manifold or spiral end of the tube and led again tothe outside through the radial end or central manifold, thus producing atemperature gradient from the warmer outer portion of the container tothe cooler inner portion of the liquid or solid acetylene-filledstabilizer. In this way the acetylene in the outer part of the packageis vaporized rst and can escape freely to the space next to the wall andthence to the valve opening. This preferred process of charging anddischarging prevents direct handling of liquid acetylene.

An alternative form of the package is illustrated in FIG. 4. Here ahighly permeable medium 16 having interconnecting pores surrounds acentral core of porous stabilizer 12 bearing, as before, a heat transfertube or plate 315. The highly permeable medium provides free flow ofgaseous acetylene to and from the porous stabilizer during charging anddischarging, and also serves as a barrier to both heat and shock duringstorage and transport. In use, only the porous stabilizer itselfcontains liquid acetylene; therefore, the highly permeable medium neednot be as effective a stabilizer for condensed acetylene as the porousstabilizer (since it needs to stabilize only the gaseous acetylene), andit can be chosen primarily for its permeability and its heat-insulatingand shock-insulating value.

Any porous insulating material such as glass wool, mineral wool, foamplastic, balsa wood, cork, kapok, or coconut husk liber could be usedprovided the container is properly designed to handle the material. Theprimary requirements are a high insulating quality to reduce heat leak,and a porous structure to form a shock barrier for the iiller core andto provide a permeable medium so that gaseous acetylene will have accessto the entire eX- terior surfaces of the core. In the containers ofFIGS. 2 and 3 the outer gas-filled portion of the stabilizer itselfserves as the permeable medium surrounding the stabilizer corecontaining condensed acetylene.

ln large packages it may be desirable to provide special gas passagesinto the interior. This may be done by dividing the porous stabilizerinto discs and putting a disc of highly permeable medium between eachtwo discs of porous stabilizer, the whole surrounded by a layer ofhighly permeable medium. Each disc of porous stabilizer would have animbedded heat-transfer tube or plate, not necessarily of the spiral formmentioned above. This form of the package, illustrated in FIG. 5, hasthe additional advantage of allowing the acetylene to be supplied over arelatively large surface of the stabilizing medium, thus increasing therate and uniformity of the condensation process.

The pressure of the gaseous acetylene in the package during transport ispreferably between atmospheric pressure and 100 p.s.i.g. At pressuresbelow atmospheric, air would tend to enter the package if leaks existed,and the safety of the system would thus decrease. At pressures higherthan about 100 p.s.i.g. the cost and weight of the container wouldbecome high and the safety would decrease. The pressure of the gas inthe package is determined by the temperature of the liquid or solid withwhich the gas is in contact. The vapor pressure of acetylene at certaintemperatures is as follows:

ince solid acetylene is stabilized by the porous iiller media of thisinvention, a cooling lluid whose temperature is lower than 84 C. may beused in charging the acetylene into the container provided the pressureof the gaseous acetylene at the inlet valve is always above atmosphericpressure. Even during storage and transport the central part of thepackage may safely contain solid acetylene at a temperature below 84 C.As discussed above the container pressure preferably is atmospheric orhigher. Since the container gas pressure is the equilibrium vaporpressure, the condensed acetylene in contact with the acetylene vapor inthe outer portion of the container should not be cooler than 84 C. inorder to maintain the gas pressure in the container at or aboveatmospheric pressure. By balancing the heat leak into the containeragainst the degree of sub-cooling below 84 C., a cooling iluid as coldas liquid nitrogen may be used for at least part of the charging. Inpractice, the acetylene may be condensed by using any cooling fluidhaving a temperature below the condensation temperature of acetylene atthe supply pressure, and conversely the use of any warming fluid havinga temperature above the vaporization temperature of acetylene at thestorage pressure will provide acetylene vapor having a pressure aboveatmospheric pressure. The vapor pressure of acetylene and consequentlythe delivery pressure of the cylinder may be regulated by varying thetemperature of the warming lluid. A cooling iluid whose temperature isabout 60 C. to 80 C., such as acetone or ethanol,

and a warming fluid having a temperature between about 45 C. and +40 C.such as acetone or ethanol may be used. Acetone is the preferred coolingand warming fluid, because of its low viscosity at low temperatures. Theabove temperature ranges are the preferred conditions for cooling andwarming.

'Io transport acetylene with as little evaporation loss as possible theheat leak into the package must be kept to Ia minimum. With any of thepackages illustrated, a layer of insulating material outside the vesselcan be used. ln the packages of FIGS. 2 and 3 the layer of gas-filledporous stabilizer acts as insulation because the porous stabilizerssuitable for use with acetylene have a much lower heat conductivity whenthe pores are iilled with gaseous acetylene than when they are filledwith liquid acetylene. As heat continues to enter the package throughthe vessel Wall from the ambient air, the layer of gaslilled porousstabilizer becomes thicker as more acetylene evaporates and the heatflow becomes less. In the package of FIG. 4 the highly permeable mediumnext to the vessel wall can be chosen on the basis of itsheat-insulating value as well as its shock-insulating value andtherefore -a lower heat leak can be expected than with the packages ofFIGS. l, 2 and 3.

It is an advantage if no acetylene is vented from the package duringstorage or transport and to this end it is desirable to have anappreciable volume of gas space in the package to provide room for theacetylene vaporized. This gas space is provided by the channels withinthe highly permeable medium and by the pores of the solid stabilizerwhich are not lilled with liquid `or solid acetylene. A relief valve canbe installed to vent gaseous acetylene when the pressure reaches apredetermined upper limit. An upper limit of about p.s.i.g. has beenconveniently used.

In order for a vliquid or solid acetylene package to be safe enough totransport, any accident reasonably to be expected should not causegeneral decomposition of the acetylene. This degree of safety can belassured in either of two ways. In the rst way the package can bedesigned so that the liquid acetylene-porous stabilizer system isabsolutely stable; that is, if any part of the acetylene-filler systemis brought, -by any means, to a temperature comparable to that developedby the decomposition of acetylene, this region of high temperaturecannot propagate through the rest of the system. In the second way theliquid acetylene yis stabilized greatly, although not completely, bylthe porous stabilizer whose pores it iills. As a result of thisincreased stability, we can isolate the acetylene-porous stabilizer massfrom outside ecomposition iniluences by surrounding it with a protectiveinsulating barrier. This invention provides both of these ways ofachieving safety by increasing the energy level required for Kacetylenedecomposition.

The liquid or solid acetylene packages of this invention |have beensubjected to rigorous safety tests. For example, a series of shock testswas carried out ou acetylene containers in which a monolithic calciumsilicate filler having a porosity of about 82% (thas is, the calciumsilicate-asbestos material occupies only 18% of the nominal volume ofthe solid, porous mass) was used as the stabilizing medium. When thepores of the porous stabilizer in the container were substantially fullof liquid acetylene (as in FIG. l), then the exploding of a charge ofdynamite just outside the container caused decomposition of some of theacetylene within; if, however, after the pores had rst beensubstantially filled with liquid :acetylene some heat had been allowedto enter the container through the wall and some acetylene had beenvaporized and withdrawn (as in FIG. 2), then the exploding of a 'chargeof dynamite just outside the container did not cause decomposition ofthe acetylene. No decomposition of the acetylene occurred in tests inwhich the pore volume of the porous stabilizer was calculated to be lled82.5% to 84.7% of capacity with liquid acety- 'i' lene. There was nodecomposition of the liquid acetylene in .similar containers when riflebullets were fired into the containers at close range. Examples I and IIillustrate the type of safety tests conducted.

Example I-Rifle-F ire Stability Tests A nearly spherical test containerof ylow-alloy steel, 11.75 inches internal diameter and 0.078-inch Wall,with a 1t-inch-thicl: plate of stainless steel inside to serve as atarget or impact plate, was filled with 82.4% porosity monolithiccalcium silicate ller. The container was evacuated to remove most of thefair and was then connected, through a cooling coil, to a supply ofgaseous acetylene. The container and coil were immersed in a solidcarbon dioxide-acetone bath and 19.75 pounds of acetylene were condensedin situ. The cooling bath was removed from around the container yandacetylene vaporized by heat from the ambient air was vented through ameter. At the end of 5 minutes, when the pore volume was calculated tobe 96.8% full of liquid acetylene, a copper-jacketed lead bulletWeighing 510 grains was shot into the container from a0.458-inch-caliber rifle Whose muzzle was three feet from the container.The gun was aimed so that the bullet struck the target plate. Noexplosion of the acetylene occurred. In tests that were similar, exceptthat no filler was present, the acetylene charge exploded in each ofthree tests.

Example II-Dynamil-fe Stability Tests A test container similar to thatof Example l, except that there was no target plate, was charged withliquid acetylene in the way described in Example I. The container wasremoved from the cooling bath and allowed to warm in the air for 1.9hours at which time 14.5 pounds of liquid acetylene were calculated toremain in the container. This amount was calculated to ll 84.7% of thepore volume of the porous stabilizer and the stabilizer/ acetyleneWeight ratio was about one. Then a 71-gram charge of 40% nitroglycerinedynamite resting against the outside surface of the container wasexploded. No dccomposition of the acetylene could be detected.

In -other experiments made under similar conditions a pore-volumefilling of 85.3% or greater sometimes led to explosion, while 84.7% orless never exploded.

The liquid acetylene in the acetylene transport packages of thisinvention is absolutely stable when the monolithic calcium silicatestabilizer has a porosity of less than about 70%. That is, the pores ofsuch a stabilizer may be completely iilled with liquid 1acetylenewithout danger of progressive decompostion of the condensed acetylene.However, it is more economical to use a monolithic calcium silicatestabilizer having a porosity greater than 80% and insure rstability byproviding a layer of stabilizer containing no liquid acetylene or aseparate layer of highly permeable material also containing no liquidacetylene next to the wall of the container.

The yrille-re and dynamite tests are of course very severe in relationto the shocks which a liquid acetylene package would be likely to sufferin commercial use.

The advantages of the acetylene package of the present invention overthe prior `art may be demonstrated by reference to an acetylenecontainer of the type shown in FIG. 5 in which the solid stabilizer is82% porosity calcium silicate and the highly permeable medium is amaterial such as foamed plastic having interconnecting pores. Such acontainer having a capacity of about 2 tons of liquid acetylene weighsabout 6 tons fully charged. This represents a pay load of acetylene ofabout 33% as cornpared to a pay load of about 10% for a currentcommercial dissolved acetylene container of comparable weight.

Also, a container of the type shown in FIG. 5 may be designed to operatewith a relief valve set to open when the pressure of gaseous acetylenereaches about 100 p.s.i.g. The construction of closable shells capableof safely withstanding a working pressure of 100 p.s.i.g. is relativelyeasy and relatively inexpensive. On the other hand, the currentcommercial dissolved acetylene cylindcr must be designed for a workingpressure of 250 p.s.i.g. with a large safety factor to allow fortransient pressures in excess of this value. (The 250 p.s.i.g. pressureis approximately the vapor pressure of acetylene dissolved in acetone at70 F. when sulicient acetylene is dissolved to give a pay load of about10%.) The construction of cylinders which will withstand pressuresgreater than 250 p.s.i.g. is relatively expensive. A container of thetype shown in FIG. 5 in which the acetylene is condensed at C. has asuiiiciently small heat leak s0 that the gaseous acetylene pressureremains less than p.s.i.g. for about 5 to l1 days, depending upon theambient temperature of its surroundings.

A still further advantage of the acetylene containers of this inventionis that a solvent is not required. Therefore, there is no acetone orother solvent which can escape during filling, storage or maintenance of'the container, no solvent vapor in the delivered acetylene and noproblem of solvent entrainment when the acetylene is withdrawn from thecontainer.

What is claimed is:

l. Process for transporting and dispensing acetylene which comprisescharging a container having a porous stabilizer with interconnectingpores therein with gaseous acetylene; cooling the interior portions ofsaid porous stabilizer below the gaseous acetylene condensationtemperature to provide a temperature gradient from the cooler interiorportions to the surface of said porous stabilizer; condensing saidgaseous acetylene in the pores of the cooler interior portions of saidporous stabilizer and distributing such condensed acetylene throughoutsaid porous stabilizer by capillary action in Ithe pores interconnectingwith the cooler interior portions of said porous stabilizer;transporting the condensed acetylene-containing porous stabilizer;Warming portions of said porous stabilizer above the condensed acetylenevaporization temperature to vaporize condensed acetylene; and dispensinggaseous acetylene from said porous stabilizer.

2. Process according to claim 1 wherein condensed acetylene is vaporizedby warming the interior portions of said porous stabilizer above thevaporization temperature of the condensed acetylene.

3. Process in accordance with claim l wherein the gas to be condensed issupplied over a substantial area of the outside surface of said porousstabilizer.

4. Process in accordance with claim l wherein a temperature gradient ismaintained from the cooler center to the warmer surface of said porousstabilizer during condensation of said gas within said pores, to provideorderly condensation starting in the pores near the cooler center andprogressing toward the warmer surface as the pores become iilled -withcondensed material.

5. Process in accordance with claim l wherein a tempcrature gradient ismaintained from the warmer surface to the cooler center of said porousstabilizer to vaporize and discharge said condensed gas from said pores,said vaporization starting in the porcs near the warmer surface andprogressing toward the cooler center of said porous stabilizer.

6. Process for the safe transportation and dispensing of acetylene `froma porous solid filler comprising the steps of charging gaseous acetyleneto such iiller for diffusion thcreinto; cooling the solid filler to atemperature below the condensation temperature of the acetylene at thecharging pressure, thereby condensing the charged gaseous acetylene byphase change; forming and maintaining a heat generated layer ofgas-lilled porous material about the outer surface of said porous solidiiller to preserve refrigeration in the condensed acetylene gasilledinterior of said filler; transporting the condensed acetylene-containingporous solid filler; dispensing gaseous acetylene from such iller byheating the filler to a temperature above the vaporization temperatureat the dispensing pressure.

7. Process for the safe transportation and dispensing of acetylene from1a solid porous ller comprising the steps of charging gaseous yacetyleneto such filler for diffusion thereinto, said porous liller havinginterconnecting pores capable of holding liquid acetylene by capillaryaction; cooling the solid filler to a temperature below the condensationtemperature of the acetylene at the charging pressure, therebycondensing the charged gaseous acetylene by phase change; `forming andmaintaining a heat generated layer of gaseous acetylene filled porousmaterial about the outer surface of said porous filler to preserverefrigeration in the condensed acetylene lled interior of said body;transporting the condensed acetylene-containing porous solid body;dispensing gaseous acetylene from such body by heating the body to aternperature above the vaporization temperature at the dispensingpressure.

References Cited in the lile of this patent UNITED STATES PATENTS FoucheNov. 6, 1900 James Mar. 29, 1909` Snelling May 12, 1914 Stephenson June19, 1917 Heylandt Mar. 14, 1933 OBrian et al. June 17, 1947 Bour Apr. 4,1950 Feick Apr. 18, 1950 Mojonnier Aug. 22, Huren Nov. 7, 1950 SpanglerDec. 22, 1953 Spangler July 12, 1955 McDonald Sept. 18, 1956 BeckwithNov. 11, 1958 Grosse et al. Mar. 15, 1960

1. PROCESS FOR TRANSPORTING AND DISPENSING ACETYLENE WHICH COMPRISESCHARGING A CONTAINER HAVING A POROUS STABILIZER WITH INTERCONNECTINGPORES THEREIN WITH GASEOUS ACETYLENE; COOLING THE INTERIOR PORTIONS OFSAID POROUS STABILIZER BELOW THE GASEOUS ACETYLENE CONDENSATIONTEMPERATURE TO PROVIDE A TEMPERATURE GRADIENT FROM THE COOLER INTERIORPORTIONS TO THE SURFACE OF SAID POROUS STABILIZER; CONDENSING SAIDGASEOUS ACETYLENE IN THE PORES OF THE COOLER INTERIOR PORTIONS OF SAIDPOROUS STABILZER AND DISTRIBUTING SUCH CONDENSED ACETYLENE THROUGHOUTSAID POROUS STABILIZER BY CAPILLARY ACTION IN THE PORES INTERCONNECTINGWITH THE COOLER INTERIOR PORTIONS OF SAID POROUS STABILIZER;TRANSPORTING THE CONDENSED ACETYLENE-CONTAINING POROUS STABILIZER;WARMING PORTIONS OF SAID POROUS STABILIZER ABOVE THE CONDENSED ACETYLENEVAPORIZATION TEMPERATURE TO VAPORIZE CONDENSED ACETYLENE; AND DISPENSINGGASEOUS ACETYLENE FROM SAID POROUS STABILIZER.